I only shoot factory, and if possible, I only shoot Remington Green Box Core-Lokt ammo. I find it to be very accurate, and perform great on game. Yea, sometimes I find that it costs $2.00 to $3.00 more than a box of Winchesters or Federals, and frankly, I don't care.
The only time I might shoot something different would be on a big-time Elk or Moose hunt, in which case I would use Hornaday factory ammo with very high grade bullets, which I believe to be superior to them all.
If you are looking for someone to tell you that all Winchester factory ammo is great stuff, . . . nobody is going to do that.
Best,
Mannyrock